Sexually transmitted hepatitis: a review

HBV infection in relation to consistent condom use: a population-based study in Peru

Background

Data on hepatitis B virus (HBV) prevalence are limited in developing countries. There is also limited information of consistent condom use efficacy for reducing HBV transmission at the population level. The study goal was to evaluate the prevalence and factors associated with HBV infection in Peru, and the relationship between anti-HBc positivity and consistent condom use.

Methods and Findings

Data from two different surveys performed in 28 mid-sized Peruvian cities were analyzed. Participants aged 18–29 years were selected using a multistage cluster sampling. Information was collected through a validated two-part questionnaire. The first part (face-to-face) concerned demographic data, while the second part (self-administered using handheld computers) concerned sexual behavior. Hepatitis B core antibody (anti-HBc) was tested in 7,000 blood samples. Prevalences and associations were adjusted for sample strata, primary sampling units and population weights. Anti-HBc prevalence was 5.0% (95%CI 4.1%–5.9%), with the highest prevalence among jungle cities: 16.3% (95%CI 13.8%–19.1%). In the multivariable analysis, Anti-HBc positivity was directly associated with geographic region (highlands OR = 2.05; 95%CI 1.28–3.27, and jungle OR = 4.86; 95%CI 3.05–7.74; compared to coastal region); and inversely associated with age at sexual debut (OR = 0.90; 95%CI 0.85–0.97). Consistent condom use, evaluated in about 40% of participants, was associated with reduced prevalence (OR = 0.34; 95%CI 0.15–0.79) after adjusting for gender, geographic region, education level, lifetime number of sex partners, age at sexual debut and year of survey.

Conclusion

Residence in highlands or jungle cities is associated with higher anti-HBc prevalences, whereas increasing age at sexual debut were associated with lower prevalences. Consistent condom use was associated with decreased risk of anti-HBc. Findings from this study emphasize the need of primary prevention programs (vaccination) especially in the jungle population, and imply that condom use promotion might be a potential strategy to prevent HBV infection.

Hepatitis B virus infection in patients attending a genitourinary medicine clinic: risk factors and vaccine coverage

BACKGROUND

The hepatitis B virus (HBV) immunisation policy in the United Kingdom includes offering vaccines selectively to those at risk by sexual contact. Among genitourinary medicine (GUM) clinic attenders, homosexual men are offered vaccine, but estimates of the vaccine uptake are required to monitor policy and estimate the possible impact on transmission; heterosexuals are not routinely offered vaccine, but this policy might change if the prevalence was found to be high.

OBJECTIVE

To determine the prevalence of HBV infection and vaccine uptake among patients attending a GUM clinic.

METHODS

HBV seroprevalence determined by unlinked anonymous testing of consecutive blood samples sent for syphilis serology. Demographic and risk factor data and history of HBV immunization extracted from clinic notes before unlinking. Prevalence data were compared with a population of first time blood donors from the same area.

SETTING

Open access GUM clinic in central London.

RESULTS

Samples were obtained and tested from 441 homosexual and 527 heterosexual men and from 821 women over a 4 month period in 1990. After exclusion of injecting drug users and their sexual partners (n = 30) and HBV carriers attending for follow up (n = 12), the prevalence of antibody to HBV core (anti-HBc) was 38.7% in homosexual men, 5.9% in heterosexual men, and 3.5% in women (50.0%, 6.0%, 3.7% respectively if previous vaccinees were also excluded). The prevalence of HBV surface antigen positivity was 4.2%, 0.60%, and 0.39% respectively after exclusion of vaccinees (chi(2) p < 0.001 for homosexual men versus others). The prevalence of the anti-HBc in first time blood donors was 1.1% (8/749). Among male GUM clinic attenders, the prevalence of anti-HBc was higher in those of non-UK origin or place of birth and/or non-white ethnicity (odds ratios 2.87, 95% CI 1.57-5.24 and 8.06, CI 3.39-19.1, in homosexuals and heterosexuals respectively). In homosexual men anti-HBc prevalence increased with age (OR 1.05, CI 1.02-1.07 for each year) and lifetime number of STDs (OR 6.36, CI 3.77-10.8 for > or = 2 versus < 2) and in clinic reattenders compared with new patients (OR 5.42, 95% CI 3.32-9.16). Among heterosexuals, age was associated with anti-HBc prevalence in women (OR 1.09, CI 1.04-1.12) but not men (OR 0.99, 95% CI 0.95-1.02). There were no other associations in heterosexuals. A history of HBV immunisation in homosexual men was recorded in 13/131 (9.9%) of new patients and 103/305 (33.8%; OR 4.63, CI 2.49-8.60) clinic reattenders.

CONCLUSIONS

Although higher than a sample of blood donors, the prevalence of serological markers of HBV infection among heterosexuals was low, providing little support for extending HBV immunisation to all heterosexuals attending GUM clinics as a targeted strategy for control of HBV infection. Homosexual men remain at high risk of infection, but many are now being immunised. Efforts to improve compliance with existing vaccine policies in GUM clinics should be encouraged.

Hepatitis B markers in heterosexual patients attending two genitourinary medicine clinics in the West Midlands

OBJECTIVE

To determine the prevalence of hepatitis B virus (HBV) infection in heterosexual patients attending two genitourinary medicine (GUM) clinics in the West Midlands and to examine whether heterosexual activity is a risk factor for acquiring HBV infection with the view to extend HBV vaccination policies to cover this group.

DESIGN

HBV markers were determined in the GUM study group and compared with that of the control groups. Responses to a questionnaire were used to examine sexual behaviour patterns that may be related to heterosexual acquisition of HBV infection.

SETTING

The West Midlands, UK April 1992-January 1993.

SUBJECTS

788 male patients and 688 female patients attending GUM clinics were compared with 498 male blood donors and 563 females attending antenatal clinics for the seroprevalence of HBV markers. Potential risk factors related to heterosexual activity were assessed in 1436 patients in the study group.

MAIN OUTCOME MEASURES

Prevalence of HBV markers in the GUM study group and the controls. The possible use of the risk factors examined as predictors for acquiring HBV infection.

RESULTS

The seroprevalence of hepatitis B core antibody (anti-HBc) in GUM patients was 1.9% and 0.5% in the control group. In the study groups the prevalence of anti-HBc from Birmingham was 3.2% while that from Coventry was 0.8%. The low seroprevalence of HBV prevented a multiple logistic analysis. A limited regression analysis showed that being non-white (p < 0.001) and duration of sexual activity (p = 0.013) were risk factors for HBV infection. However, these two factors were poor predictors of the risk to exposure to HBV infection.

CONCLUSION

The prevalence of HBV infection in heterosexual patients in the West Midlands is very low and does not provide any indications to broaden HBV vaccination into heterosexual patients attending GUM clinics. Risk factors were poor predictors of the exposure to HBV infection. This is partially due to the low prevalence of HBV infection in this study. Further studies are required before definitive conclusions are made regarding the potential predictive value of risk factors.